The present invention relates to an air-insulated high-voltage disconnector.
A disconnector includes, in particular, a pivotally-mounted arm, sometimes referred to as a xe2x80x9cknifexe2x80x9d, mounted to pivot about a horizontal axis and electrically connected at one of its ends to a first connector disposed at the top of a first insulating column. The other end of the arm, i.e. the free end, is provided with a contact part or xe2x80x9chammerxe2x80x9d which, when the disconnector is in the closed position, co-operates with a jaw connected to a second connector disposed at the top of a second insulating column.
During disconnector closure, once the pivotally-mounted arm has been lowered, it is then turned about its axis through 90xc2x0, thereby bringing the hammer into contact with the contact parts of the jaw.
The jaw is made up of two facing parallel rows of contact parts, each part being formed of a curved copper blade fixed to a jaw support. The hammer, which extends the arm at its end, is a part made of bronze that is heavy and costly and whose section in a plane perpendicular to the axis of the arm corresponds to a circle of diameter smaller than the diameter of the arm and that is flattened along one diameter so that it is extended to coincide with the diameter of the arm, the thickness of the two diametrically opposite extensions being in the range 2 mm to 3 mm, with rounded edges.
French Patent 2 674 985 describes such a disconnector.
The present invention proposes to improve certain features of a disconnector of that type, and it provides an air-insulated high-voltage disconnector including a pivotally-mounted arm suitable for pivoting at one of its ends about a horizontal axis that is perpendicular to the axis xcex94 of the arm, and also suitable for turning about its own axis xcex94, the free end of the arm carrying a contact part or xe2x80x9chammerxe2x80x9d which, when the disconnector is in the closed position, co-operates with a jaw comprising a jaw support to which two facing rows of contact fingers are fixed, wherein the hammer is equipped with contact tabs co-operating with the contact fingers, each contact tab forming a wedge of angle xcex2, which wedge acts, during disconnector closure, to meet the corresponding row of fingers with an angle of attack xcex1, said angle of attack xcex1 being less than 90xc2x0.
Advantageously, the angle xcex2 is approximately in the range 30xc2x0 to 40xc2x0, and the angle xcex1 is about 60xc2x0.
According to another characteristic, each contact tab is provided with a curved contact face extending over an angle xcex4, seen from the axis xcex94 of the arm, this angle xcex4 being about 17xc2x0.
According to another characteristic, when the wedge of a contact tab comes into contact with one of said contact fingers, the angle xcex3, seen from the axis xcex94 of the arm, between the point of contact and the plane perpendicular to the contact finger containing the axis xcex94, is about 10xc2x0.
According to another characteristic, said contact fingers are fixed to the jaw support so that, when the disconnector is in the closed position, the angle E between the axis xcex94 of the arm and the contact fingers is greater than 90xc2x0.
According to another characteristic, said facing fingers form an angle xcfx86 between them that lies in the range 2xc2x0 to 6xc2x0.
According to another characteristic, said contact fingers are tubular and open at both of their ends.
According to another characteristic, a locking abutment is fixed to a contact finger at a level situated above said hammer when the disconnector is in the closed position.